Zebra ZD620 troubleshooting guide: errors, faults and fixes

Short answer: The cover is not fully latched, or the head-open switch needs repairing. Press on both front corners of the cover until the latches click into place; if the alert persists with the cover closed, Zebra asks you to call a technician.

Likely cause

According to the Zebra guide, the alert appears when the cover is open or not properly closed at the time of a print command or a press on FEED. Zebra cites a second cause: the head-open switch, which needs repairing.

What to do

1. Press firmly on both front corners of the cover until the latches click into place.
2. Restart printing: a solid green STATUS light indicates that the printer is ready.
3. If the alert is still displayed while the cover is properly latched, the head-open switch is at fault.

When to call a technician: if the alert persists with the cover latched, Zebra states that the head-open switch must be repaired by a technician.

Sources: Resolve Alerts and Errors (opens in a new window) · Standard Interface Controls (opens in a new window) · Status – Typical Operating Conditions (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The ZD620 no longer detects labels: empty roll, missing label on the liner, or sensor badly positioned or dirty. Reload the roll, close the cover and press FEED once; if labels are present, check the position of the movable sensor and run a SmartCal calibration again.

Likely cause

The Zebra guide lists six causes: no media loaded; a missing label, which marks the end of the roll; a misaligned media sensor; a printer set for non-continuous media when continuous media is loaded; a dirty sensor; faulty detection (corrupted memory data or defective component).

What to do

1. Empty roll: remove the rest of the media and the core, fit a new roll, close the printer and press FEED once. Do not switch off the printer to reload, so as not to lose the current job.
2. Label missing in the middle of the roll: pull the media through until the next label is on the platen roller, close the printer and press FEED once to resynchronise.
3. Black mark or notched media: centre the movable sensor arrow on the mark or notch, then run a SmartCal calibration again if necessary.
4. Continuous media loaded while the printer expects labels: return the sensor to its default centre position, then recalibrate.
5. Dirty sensor: clean the upper gap sensor and the lower movable sensor, reload the media, set the sensor and recalibrate.
6. If detection still does not work, reload the firmware (see firmware update).

When to call a technician: if the alert persists after reloading the firmware, Zebra asks you to call a technician.

If you switch to different media (size, supplier or batch), Zebra asks you to calibrate the printer for this new media.

Sources: Resolve Alerts and Errors (opens in a new window) · Recovering from a Media-Out Condition (opens in a new window) · Standard Interface Controls (opens in a new window) · Adjusting the Movable Sensor for Black Marks or Notches (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: In thermal transfer, the ZD620t has detected the end of the ribbon: genuine Zebra ribbons end with a reflective trailer, which is read as the end of the ribbon. Remove the used ribbon, load a new roll, close the cover and press FEED once.

Likely cause

According to Zebra, the printer has detected the end of the ribbon roll thanks to the reflective trailer on Zebra ribbons. For ribbon roll models, the guide also cites faulty detection linked to another problem.

What to do

1. Open the printer: the reflective section that signals the end of the ribbon is visible.
2. Remove the used ribbon from the take-up spindles and throw it away.
3. Fit a new roll of ribbon following the loading procedure in the Zebra guide.
4. Close the printer and press FEED once; you may need to press PAUSE to resume an interrupted job.
5. If the alert persists with a new ribbon correctly loaded, reload the firmware (see firmware update).

When to call a technician: if the alert persists after reloading the firmware, Zebra asks you to call a technician.

This alert applies to the ZD620t, which prints in thermal transfer with a ribbon roll. The Zebra guide does not describe it for the ZD620d (direct thermal).

Sources: Resolve Alerts and Errors (opens in a new window) · Recovering from a Ribbon-Out Condition (opens in a new window) · Standard Interface Controls (opens in a new window) · Status – Typical Operating Conditions (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The cutter blade is jammed by media, adhesive or a foreign object. Switch off the ZD620 by holding POWER for 5 seconds, wait until it has shut down completely, then switch it back on; if it does not recover, call a technician.

Likely cause

Zebra states that the cutter blade is blocked and no longer moves correctly, obstructed by media, adhesive or a foreign object.

Caution: The cutter has no operator-serviceable parts. Zebra prohibits removing its cover and inserting objects or fingers into the mechanism. Unapproved tools, cotton buds and solvents (including alcohol) can damage it or cause jams.

What to do

1. Hold down the POWER button for 5 seconds to switch off the printer.
2. Wait until it has shut down completely, then switch it back on.
3. If the printer does not recover, do not try to free the blade yourself: the cutter has no user-serviceable parts.

When to call a technician: if the printer does not recover after a restart, Zebra asks you to call a technician.

Sources: Resolve Alerts and Errors (opens in a new window) · Standard Interface Controls (opens in a new window) · Status – Typical Operating Conditions (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The printhead is too hot, usually during a long job: the ZD620 pauses to let it cool down. Printing resumes by itself once the printhead has cooled; if the room is too hot, move the printer.

Likely cause

According to Zebra, the printhead gets too hot during a large batch of labels, or the ambient temperature exceeds the operating range, for example because of direct sunlight.

Caution: Zebra warns that the printhead can be hot enough to cause severe burns: let it cool down before touching it.

What to do

1. Leave the printer paused: printing resumes automatically when the printhead has cooled down.
2. If the ambient temperature is the cause, move the printer out of direct sunlight or cool the room.

Sources: Resolve Alerts and Errors (opens in a new window) · Status – Printhead Operation (opens in a new window) · Standard Interface Controls (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The printhead has overheated or suffered a critical failure: the printer must cool down and then restart. Switch it off by holding POWER for 5 seconds, wait several minutes, then switch it back on; if the error returns, call a technician.

Likely cause

Zebra describes three related situations: the printhead has overheated (Printhead Shutdown); the printhead has been subjected to a critical temperature or a power cut; the printhead thermistor is faulty. The guide specifies that STATUS and PAUSE flash red during overheating that requires cooling and a restart.

Caution: Zebra warns that the printhead can be hot enough to cause severe burns: let it cool down before touching it.

What to do

1. Hold down POWER for 5 seconds and wait until the printer has shut down completely.
2. Let the printhead cool down completely for several minutes.
3. Switch the printer back on.
4. If the error reappears, do not work on the printhead: Zebra specifies that it cannot be repaired by the operator.

When to call a technician: if the error persists after a restart (overheating, critical temperature, power cut or thermistor), Zebra asks you to call a technician.

Sources: Resolve Alerts and Errors (opens in a new window) · Status – Printhead Operation (opens in a new window) · Standard Interface Controls (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The printhead is below its operating temperature, often because the room is colder than the specified minimum. Switch off the ZD620, install it in a warmer place and let it warm up naturally.

Likely cause

According to Zebra, the printhead is too cold to print correctly, usually because the environment is below the minimum operating temperature.

Caution: Zebra warns that moving too quickly from cold to warm can cause condensation inside the printer.

What to do

1. Switch the printer off.
2. Install it in a warmer place.
3. Let it warm up by itself before switching it back on.

Sources: Resolve Alerts and Errors (opens in a new window) · Status – Printhead Operation (opens in a new window) · Standard Interface Controls (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The ZD620 no longer has enough memory to store a format, graphic or font. Simplify the label and delete unused graphics, fonts or formats.

Likely cause

Zebra states that the memory (graphics, formats, bitmaps or fonts) is insufficient for the requested function.

What to do

1. Reduce the label format or the print area.
2. Delete graphics, fonts and formats that are no longer used from the memory.
3. Check that the data is not being sent to a device that is not installed or is unavailable.

Sources: Resolve Alerts and Errors (opens in a new window) · Standard Interface Controls (opens in a new window) · Status – Typical Operating Conditions (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Run a SmartCal calibration: with the printer ready, hold PAUSE and CANCEL down for 2 seconds, then release. The ZD620 measures a few labels and sets its detection; the STATUS light returns to solid green at the end.

Likely cause

SmartCal calibration measures the media and detects its type: labels separated by gaps, black mark or notched media, or continuous media. Zebra states that there is no need to recalibrate for a new batch of the same type of media: the printer adjusts during printing.

Official SmartCal calibration procedure

1. Check that the media, and the ribbon on a ZD620t, are correctly loaded, then close the cover.
2. Switch on the printer with POWER and wait for the Ready state: STATUS light solid green.
3. Hold PAUSE and CANCEL down together for 2 seconds, then release.
4. The printer measures several labels and adjusts its detection levels, then the STATUS light returns to solid green.

For a new roll from the same batch, Zebra states that pressing FEED once or twice is enough to resynchronise the labels. If SmartCal does not recognise the media, use manual calibration.

Sources: Running a SmartCal Media Calibration (opens in a new window) · Resolve Print Issues (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Enter advanced mode (PAUSE held for 2 seconds), start manual calibration with PAUSE, then have the printer measure the liner alone, then a label. Zebra reserves this method for media that automatic calibration does not recognise correctly.

Likely cause

Some media are not correctly recognised by automatic calibration; the Zebra guide then provides a manual calibration from advanced mode.

Official manual calibration procedure

1. With media loaded and the printer switched on, hold PAUSE down for 2 seconds: all lights flash yellow, then STATUS stays solid yellow (manual calibration mode).
2. Press PAUSE: SUPPLIES flashes yellow, then PAUSE flashes.
3. Open the printer and check the movable sensor: centre position (alignment arrow) for labels with gaps, on the mark or notch for black mark media, and at the point where it detects the least print for pre-printed media.
4. Peel about 80 mm of labels off the liner.
5. Lay the section without labels over the platen roller, with the leading edge of the first label under the guides.
6. Close the printer and press PAUSE once: the media light flashes while the liner is measured, then PAUSE starts flashing.
7. Open the printer and advance the media to place a label just above the movable sensor.
8. Close the printer and press PAUSE once: the printer feeds and measures several labels, then returns to the Ready state if it has determined the media type and length.

Zebra specifies that you may need to repeat the procedure several times, moving the sensor at each attempt, until the printer returns to the Ready state. To exit advanced mode, press CANCEL.

Sources: Activating Advanced Mode (opens in a new window) · Manually Calibrating Media (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Zebra calls this a registration fault: media loaded incorrectly, movable sensor badly positioned or sensors not calibrated for the media. Check the sensor position, then run a SmartCal calibration; if the skipping continues, perform a manual calibration.

Likely cause

The Zebra guide cites four causes: media loaded incorrectly or movable sensor set incorrectly; sensors not calibrated for the length, properties or detection type of the media; platen roller slipping or damaged; communication problem (cables or settings).

What to do

1. Check how the roll is loaded and the position of the movable sensor for your media type (see loading labels).
2. Run a SmartCal calibration.
3. If labels are still being skipped, run a manual calibration.
4. If the platen roller is slipping or damaged, clean or replace it (see platen roller).
5. If the fault appears after a few correct labels, check communication (see incomplete or distorted labels).

Sources: Resolve Print Issues (opens in a new window) · Loading Media (opens in a new window) · Running a SmartCal Media Calibration (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The printer has not been calibrated for this media or is set to continuous media. Check the MEDIA TYPE parameter in the Settings menu on the display, then run a SmartCal calibration.

Likely cause

According to Zebra, the printer has not been calibrated for the media loaded, or it is configured for continuous media.

What to do

1. On the ZD620 display, open the Settings menu and check the MEDIA TYPE parameter (gaps or notches, continuous, marks).
2. Run a SmartCal calibration.
3. For media that is difficult to calibrate, use manual calibration.

Sources: Resolve Miscellaneous Issues (opens in a new window) · Running a SmartCal Media Calibration (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Open the printer, place the roll on its holders with the printable side facing up, pass the media under both guides and position the movable sensor according to the media type. The roll must turn freely without touching the bottom of the compartment.

Likely cause

Incorrectly oriented media or a badly positioned sensor is among the causes Zebra gives for the Media Out alert, skipped labels and blank labels.

Official loading procedure

1. Open the printer by pulling the release levers towards the front.
2. Pull apart the roll holders and orient the roll so that the printable side faces up as it passes over the platen roller.
3. Pull the guides apart, place the roll on its holders, then release the guides; check that the roll turns freely and does not rest on the bottom of the compartment.
4. Pull the media so that it sticks out at the front of the printer, then slide it under both media guides.
5. Set the movable sensor: default centre position for labels separated by gaps and for continuous media; for media with black marks, notches or holes, centre the sensor arrow on the mark, as far from the edge as possible as long as the mark completely covers the sensor window.
6. For media of a different type or from a different batch, then run a SmartCal calibration.

Zebra points out that the media can shift sideways by about 1 mm during printing: take this into account when positioning the sensor. Keep the off-centre sensor position for black mark media. Models fitted with the cutter have a dedicated loading procedure in the Zebra guide.

Sources: Loading Media (opens in a new window) · Adjusting the Movable Sensor for Black Marks or Notches (opens in a new window) · Setting Media Sensing by Media type (opens in a new window) · Recovering from a Media-Out Condition (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Zebra first cites incorrectly set darkness or speed, then a dirty printhead. Print the print quality report to choose darkness and speed, then clean the printhead with a new cleaning pen.

Likely cause

The Zebra guide lists four causes: print darkness and/or speed set incorrectly; dirty printhead; dirty or damaged platen roller; worn or damaged printhead.

Caution: The printhead gets hot during printing: avoid touching it. Zebra asks you to apply anti-static precautions for any work on the printhead or on the components under the cover.

What to do

1. Print the print quality report (FEED self test): the ZD620 prints a series of labels from -3 to +3 around the current darkness, at two speeds; keep the setting whose barcodes are compliant. The Configure Print Quality function in Zebra Setup Utilities is used for the same adjustment.
2. Do not exceed the maximum speed specified by the media manufacturer.
3. Clean the printhead with a new cleaning pen (frequency in the note below).
4. If the fault persists, clean or replace the platen roller.
5. If the printhead is worn or damaged, the Zebra guide provides for its replacement.

Zebra advises cleaning the printhead with each new roll of media for optimum print quality; its recommended cleaning schedule specifies cleaning after every five rolls printed. Do not use a pen that has already been used: it carries contaminants that can damage the printhead.

Sources: Resolve Print Issues (opens in a new window) · Cleaning the Printhead (opens in a new window) · Recommended Cleaning Schedule (opens in a new window) · Cleaning Supplies (opens in a new window) · Printing a Print Quality Report (FEED Self-Test) (opens in a new window) · Adjusting the Print Quality (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Enter advanced mode, select manual darkness adjustment (DATA light yellow) and press PAUSE: the ZD620 prints increasingly dark test patterns. Press FEED as soon as a pattern shows solid, even black lines.

Likely cause

According to Zebra, each type of media may require a different darkness: quality depends on the combination of heat (darkness), speed and media.

Official manual darkness adjustment procedure

1. With media loaded and the printer switched on, hold PAUSE for 2 seconds to enter advanced mode.
2. Press FEED to move from one mode to the next until the DATA light is lit yellow (manual darkness adjustment).
3. Press PAUSE: the printer prints a pattern with the current darkness number and several barcodes, pauses, then starts again at the next darkness level.
4. As soon as a pattern shows solid, even black lines, press FEED: the darkness is saved and the printer returns to the Ready state.

Speed is set in the Windows driver or in software such as ZebraDesigner. To exit advanced mode without changing anything, press CANCEL.

Sources: Activating Advanced Mode (opens in a new window) · Manual Print Darkness Adjustment (opens in a new window) · Adjusting the Print Quality (opens in a new window) · Printing a Print Quality Report (FEED Self-Test) (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The ribbon (wax, wax-resin or resin) may not be suited to the media, or the power supply may be the wrong one. Reduce the speed without exceeding the maximum speed recommended for the ribbon, and check that you are using the power supply delivered with the printer.

Likely cause

Zebra cites two causes in thermal transfer: a ribbon incompatible with the media and the use of the wrong power supply.

What to do

1. Set the print speed no higher than the maximum speed recommended for your ribbon.
2. Check that the ribbon (wax, wax-resin or resin) suits the media (paper, coated paper or synthetic).
3. Check that the power supply is the one supplied with the printer.

The Zebra guide gives the speed instruction in relation to the ZD420 ribbon cartridge; it also points out that media manufacturers may recommend speeds lower than the printer's maximum.

Sources: Resolve Print Issues (opens in a new window) · Adjusting the Print Quality (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The media is not suited to the print mode or is loaded upside down. A ZD620d requires direct thermal media; in all cases, the printable side must face the printhead.

Likely cause

According to Zebra, the media loaded does not match the print type (media not intended for thermal transfer or for direct thermal), or it is loaded incorrectly.

What to do

1. Check that the media matches your model: direct thermal media for the ZD620d, thermal transfer media with ribbon for the ZD620t.
2. Reload the roll with the printable side facing up, towards the printhead (see loading labels).

Sources: Resolve Print Issues (opens in a new window) · Loading Media (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Remove the platen roller by releasing its two latches, clean it from the centre towards the edges with a swab lightly moistened with 99% isopropyl alcohol, then refit it. Leave to dry for one minute before reloading.

Likely cause

Zebra states that a slipping platen roller can distort the print or stop the media from feeding; it is cleaned as needed, when print quality drops.

Caution: Never re-moisten a swab or cloth that has already been used. After a jam or if there is a lot of adhesive, repeat with a new swab.

Official roller cleaning procedure

1. Open the cover (and the label dispenser door if there is one), then remove the media from the roller area.
2. Pull the release tabs on the right and left bearings towards the front, then rotate them upwards.
3. Lift the roller out of the lower frame, then slide the gear and both bearings off the shaft.
4. Clean the roller from the centre outwards with a fibre-free swab or a lint-free cloth very lightly moistened with 99% isopropyl alcohol; change swabs until the entire surface is clean.
5. Put the bearings and gear back on the shaft, position the roller with the gear on the left and lower it into the frame.
6. Fold the tabs back towards the rear until they click into place, then leave to dry for one minute before closing or loading labels.

Roller for linerless media: do not clean it with a product or by rubbing, or it will be permanently damaged. Zebra asks you to press the adhesive side of a piece of linerless media against it to remove particles, and to replace the roller if the media sticks.

Sources: Cleaning and Replacing the Platen (opens in a new window) · Recommended Cleaning Schedule (opens in a new window) · Cleaning Supplies (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The ZD620 does not recognise the installed printhead: it is not a genuine Zebra printhead, or it is installed incorrectly and the printer cannot read its resolution. Install a genuine Zebra printhead following the replacement procedure in the guide.

Likely cause

According to Zebra, “Unauthorized Printhead Error” indicates a printhead that is not a genuine Zebra printhead. “Printhead Resolution Error” indicates that the printer cannot read the resolution (dpi) of the printhead, probably because it is installed incorrectly or is not a Zebra printhead.

Caution: Before any work on the printhead, unplug the printer, let it cool down and work in an anti-static area (grounded conductive mat, anti-static wrist strap), as Zebra requires.

What to do

1. Check that the installed printhead is a genuine Zebra printhead.
2. If the printhead has just been replaced, redo its installation following the printhead replacement procedure in the Zebra guide.
3. Printing can only resume with a genuine Zebra printhead that is correctly installed.

Sources: Status – Printhead Operation (opens in a new window) · Standard Interface Controls (opens in a new window) · Replacing the Printhead (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The USB cable was probably connected before the Zebra driver was installed, and Windows installed its generic driver. Disconnect the USB cable, remove the Zebra icons from the “Unspecified” section, install the latest Zebra driver and then reconnect the cable.

Likely cause

Zebra explains that if the printer is connected via USB before the driver is installed, Windows assigns it its generic driver and the Windows test page does not print.

What to do

1. Disconnect the USB cable from the computer.
2. Open Control Panel > Devices and Printers: incorrectly installed Zebra printers appear under “Unspecified” with a ZTC prefix.
3. Remove these Zebra icons.
4. Install the latest Zebra Windows printer driver.
5. Reconnect the USB cable: the ZD620 should appear in the Printers section.

Source: Resolve Communication Issues (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The data is not reaching the printer: incorrect communication settings or unsuitable serial cable. Check the driver or software settings and, for a serial connection, match the handshake protocol and port settings to those of the computer.

Likely cause

Zebra cites incorrect communication settings, or a serial cable that is not a standard DTE or DCE type, is damaged or is too long for the RS-232 standard. The DATA light flashes green when data is being received.

What to do

1. Check the communication settings in the printer driver or software.
2. For a serial connection, check that the handshake protocol and the printer's serial port settings match those of the computer.
3. Use a standard DTE or DCE cable, replace it if it is damaged and respect the maximum length specified by the RS-232 standard.

Sources: Resolve Communication Issues (opens in a new window) · Standard Interface Controls (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Zebra blames the serial communication settings, prefix and delimiter characters that differ from those in the format, or incorrect data. Compare these settings with the computer and the label format; the communication diagnostics test shows what the printer receives.

Likely cause

The Zebra guide cites incorrect serial settings (flow control, protocol), prefix and delimiter characters that do not match the label format, and incorrect data sent to the printer.

What to do

1. Check in the driver or software that the flow control and other serial settings match those of the computer.
2. Compare the printer's ZPL prefix (COMMAND CHAR) and delimiter (DELIM./CHAR) characters with those in the label format.
3. Check the label format using the Zebra ZPL programming guide.
4. Run the communication diagnostics test: with media loaded and a print width equal to or less than that of the test label, hold PAUSE and FEED for 2 seconds (STATUS alternates green and yellow).
5. The printer prints each character received in ASCII with its hexadecimal value. The codes FE (framing error), OE (overrun), PE (parity) or NE (noise) indicate communication settings that need correcting. To exit the mode, hold PAUSE and FEED for 2 seconds again, or switch the printer off and on again.

Sources: Resolve Communication Issues (opens in a new window) · Performing a Communication Diagnostics Test (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: A solid red NETWORK light indicates an Ethernet or Wi-Fi connection fault: the printer is not on the network. If the network settings are the cause, Zebra provides for restoring them to factory values with the RESET button (6 to 10 seconds) or with PAUSE and CANCEL at power-on.

Likely cause

According to Zebra, a solid red NETWORK light indicates an Ethernet or Wi-Fi link error: the printer is not connected to the network.

What to do

1. Identify the state of the NETWORK light: solid red = Ethernet or Wi-Fi fault; flashing red then flashing yellow = Wi-Fi association then authentication in progress; flashing green = Wi-Fi connected with a weak signal; solid green = 10/100 Ethernet or Wi-Fi with a good signal; solid yellow = 10Base Ethernet; off = no Ethernet connection.
2. If the light flashes red then yellow, let Wi-Fi association and authentication finish.
3. To restore only the network settings to factory values: switch off the printer, hold PAUSE and CANCEL, switch it back on and keep both buttons held down until only the STATUS light stays on.
4. Another method: press the RESET button under the printer for 6 to 10 seconds (with a paper clip); the printer drops its connection, restores its factory network settings and prints the printer and network configuration reports.

The print server access credentials are not reproduced here: refer to the Zebra guide.

Sources: Standard Interface Controls (opens in a new window) · Status – Wi-Fi (WLAN) Option (opens in a new window) · Status – Ethernet (LAN) Option (opens in a new window) · Resetting the Printer's Network Settings to Their Factory Defaults (opens in a new window) · RESET Button Functions (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Only clean the plastic surfaces of the media path, at the cutter entry and exit, with a lint-free swab or cloth lightly moistened with 99% isopropyl alcohol. Do not touch the blades or the mechanism.

Likely cause

Zebra specifies that the blade has a special coating that resists adhesives and wear: it needs no maintenance cleaning, and cleaning it can damage it.

Caution: Never clean the internal blades or the cutting mechanism. The cutter has no operator-serviceable parts: never remove its cover and never insert objects or fingers into the mechanism. Zebra warns that unapproved tools, cotton buds and solvents (including alcohol) can damage the cutter or cause jams.

Official cutter cleaning procedure

1. Lightly moisten a clean swab or a lint-free cloth with 99% isopropyl alcohol.
2. Wipe the ribs and plastic surfaces of the media entry (inside the cutter) and of the exit slot (outside).
3. Repeat as often as necessary to remove the adhesive or residue.
4. Let the cutter dry.

When to call a technician: for any cutter maintenance beyond cleaning its surroundings, the Zebra cleaning schedule refers you to a technician.

Sources: Cleaning the Cutter Option (opens in a new window) · Recommended Cleaning Schedule (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: First check that the green light on the power supply is on: it indicates that the mains socket is supplying power. Then press POWER until the lights flash; at the end of the self-test, STATUS stays lit green.

Likely cause

The Zebra guide describes connecting the power supply, powering on and the self-test that accompanies it. With the optional battery base, a flat battery prevents power-on.

Caution: Do not use the printer or the power supply where they can get wet: Zebra warns of a risk of serious injury. Use a cord with a three-pin plug and an IEC 60320-C13 connector, and position the printer so that the cord can be unplugged easily.

What to do

1. Check the connections: power supply connected to the printer's DC socket, mains cord connected to the power supply and then to a wall socket.
2. Look at the power supply light: it lights green if the mains socket is live.
3. Press POWER until the lights flash: the power-on self-test lasts a few seconds, then only STATUS stays on, solid green.
4. With the optional battery base: press the battery button to wake it (its lights flash three times), then switch on the printer within a minute. If no charge bar lights up, the battery needs recharging and the printer cannot start.

Sources: Attaching the Printer to Power (opens in a new window) · Standard Interface Controls (opens in a new window) · Power-On Self Test (opens in a new window) · Battery Indicators and Controls (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: A solid red health light indicates an internal error: Zebra states that the battery is at the end of its life or faulty and must be replaced. Flashing red indicates a charging error, for example a battery that is too hot or too cold: let it return to room temperature and then recharge it.

Likely cause

According to Zebra, a red health light corresponds to a battery at the end of its useful life or to a component failure; flashing red corresponds to a charging error (temperature too high or too low, or internal monitoring error).

What to do

1. Solid red health light: remove the battery and replace it.
2. Battery too hot or too cold: remove it from the printer and check its condition by recharging it.
3. Let it cool down or warm up to room temperature, then check the charge again.
4. If neither the charge nor the temperature is the cause, replace the battery.

A green health light indicates a battery in good condition and charged; yellow, charging in progress. According to Zebra, a fully discharged battery recharges in about two hours and does not charge during printing.

Sources: Resolve Miscellaneous Issues (opens in a new window) · Battery Indicators and Controls (opens in a new window) · Printing with the Attached Battery Base and Battery Option (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Download the firmware from the Zebra support page for your model, then send it with Zebra Setup Utilities (Open Printer Tools > Action > Send file). The DATA light flashes green during the transfer; a configuration report prints at the end of the update.

Likely cause

Zebra recommends updating the firmware regularly. The guide also asks you to reload it when media or ribbon detection remains faulty, when settings are lost or when the printer locks up.

Official update procedure

1. Download the firmware from the Zebra support page for your model (zebra.com/zd620t-info or zebra.com/zd620d-info).
2. Open Zebra Setup Utilities and select your printer.
3. Click Open Printer Tools, then the Action tab.
4. Load media into the printer.
5. Click Send file, then the browse button (...) and choose the downloaded firmware file.
6. Wait: DATA flashes green during the download, the printer restarts with all lights flashing, STATUS stays solid green during validation and installation, then a configuration report prints.

The firmware is only transferred if its version differs from the one already installed.

Sources: Updating Printer Firmware (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide · ZD620 and ZD420, Link-OS 4-inch desktop printers, user guide (P1131665-01FR) (opens in a new window) – Zebra ZD620 and ZD420 user guide (French PDF) · Resolve Alerts and Errors (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide · Resolve Miscellaneous Issues (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Press the RESET button under the printer for 1 to 5 seconds with a paper clip: the ZD620 returns to factory defaults and prints its configuration report. Zebra Setup Utilities can also reload the default values (Open Printer Tools > Action > Load printer defaults).

Likely cause

The Zebra guide suggests restoring factory defaults when settings are lost or ignored, or when the printer locks up.

Official reset methods

1. RESET button, under the printer (press it with a paper clip): pressing for 1 to 5 seconds resets the printer to factory defaults, then it prints a configuration report (and a network report if it is connected to a network).
2. Pressing for 6 to 10 seconds (networked printers): only the network settings return to factory values; the printer prints the printer and network configuration reports.
3. Beyond 10 seconds, the printer exits reset mode without changing anything; a press of one second or less has no effect.
4. From a computer: in Zebra Setup Utilities, open Open Printer Tools, Action tab, then Load printer defaults.
5. For the network settings only, without the RESET button: with the printer switched off, hold PAUSE and CANCEL, switch it back on and keep the buttons held down until only STATUS is lit.

Sources: RESET Button Functions (opens in a new window) · Resolve Miscellaneous Issues (opens in a new window) · Resetting the Printer's Network Settings to Their Factory Defaults (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: The changes may not have been saved (^JU command not sent before switching off) or a command in the format cancels them. Switch off and on again to check that they were saved, check the commands sent, then reload the default values or the firmware if needed.

Likely cause

Zebra cites: settings configured incorrectly; changes not saved (^JU command not used before switching off); syntax errors or commands in the format that disable or reset a setting; prefix and delimiter characters that differ from those in the format; a faulty main logic board (MLB), due to corrupted firmware or a hardware failure.

What to do

1. Switch the printer off and on again to check that the settings were saved.
2. Check the syntax and use of the commands in the ZPL programming guide.
3. Compare the printer's control, command and delimiter characters (configuration report, or Language menu on the display) with those in the label format.
4. Reload the default values with Zebra Setup Utilities (Open Printer Tools > Action > Load printer defaults).
5. Reload the firmware (see firmware update).

When to call a technician: if the problem persists, Zebra asks you to call a technician: the main logic board cannot be repaired by the user.

Source: Resolve Miscellaneous Issues (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).

Short answer: Zebra suggests corrupted printer memory. Reload the default values with Zebra Setup Utilities, then reload the firmware; if the printer does not recover, call a technician.

Likely cause

According to the Zebra guide, the printer's memory may be corrupted.

What to do

1. Reload the default values with Zebra Setup Utilities: Open Printer Tools > Action > Load printer defaults.
2. Reload the firmware (see firmware update).

When to call a technician: if the printer does not recover, Zebra asks you to call a technician: the memory cannot be repaired by the user.

Source: Resolve Miscellaneous Issues (opens in a new window) – ZD620 and ZD420 Desktop Printers User Guide (official documentation).